In a network evolution process of a Long Term Evolution (LTE for short)/LTE-Advanced (LTE-A for short) system of the 3rd Generation Partnership Project (3GPP for short), an evolution trend from a homogeneous network to a heterogeneous network is shown. In the homogeneous network, a high power macro base station with a relatively large coverage area forms continuous coverage in a cellular network shape. In the heterogeneous network, more small cells are increased on the basis of the coverage of the macro base station to further increase a network capacity. With an increase in a wireless system capacity requirement, small cell intensification is one of main technical directions for satisfying the capacity requirement.
However, there are plenty of actual difficulties in a specific implementation process of small cell intensification. How to address data backhaul of a large quantity of small cells is one of key problems. The data backhaul herein generally refers to data transmission between an access point (AP) such as a small cell and a core network (Core Network). In the prior art, the data backhaul may be implemented in a wired manner, or the data backhaul may be implemented in a wireless manner. From perspectives of connection stability and a backhaul capacity, a wired backhaul manner is used by the small cell to complete backhaul. However, deploying a wired connection, such as a fiber, requires slotted construction. A city area in which small cells need to be deployed intensively usually does not have a condition for slotted construction, and the wired connection cannot be deployed. In this case, in a network, maybe only some small cells can perform data backhaul by using the wired connection, and other small cells have to complete backhaul in a wireless manner.
In a wireless backhaul technology, a relay technical solution provided by LTE is usually used to implement backhaul of a small cell. The relay technical solution includes a relay node, a terminal device, and a host node (Donor-eNB) that is connected to a core network. The relay node establishes a wireless connection with the host node by using a Un interface when backhaul needs to be performed, and completes backhaul by using the host node. The host node may be a macro base station, and the relay node may be a small cell.
Because a relationship between the host node and the relay node is one-to-many, multiple relay nodes need to complete backhaul by using a same host node. In an actual situation of intensive small cell deployment, because there are many relay nodes connected to the host node, to ensure that all the relay nodes can implement backhaul, a data transmission rate that can be supported between the host node and each relay node is limited. When a data amount of backhaul data of the relay node is relatively large, a backhaul capability may be inadequate because of a limitation of the data transmission rate, thereby affecting data backhaul.